Safety and control mechanism for power-operated structure



y 1965 -F. w. MOORE ETAL 3,181,921

SAFETY AND CONTROL MECHANISM FOR POWER-OPERATED STRUCTURE Filed Feb. 3.1964 3 Sheets-Sheet 1 INVENTORS FRED W. MOORE mafia TTORNEY QROBERT C.PRESSLEY TR.

- 1965 F. w. MOORE ETAL 3,181,921

smawy AND CONTROL MECHANISM FOR POWER-OPERATED STRUCTURE Filed Feb. ":5.1964 s Sheets-Sheet 2 2o 22 Z l 2s Fl (-3 3 INVENTORS F-RED w. MOORE H8: ROBERT c. PRESSLEY :12)

' THEIR ATroRmEY May 4, 1965 F. w. MOORE ETAL 3,131,921

SAFETY AND CONTROL MECHANISM FOR POWER-OPERATED STRUCTURE Filed Feb. 3.1964 :s Sheets-Sheet s Z0 22 Z I F'IGA 13 FIGS INVENTORS FRED w. MOOREBYZROBERT c. PRESSLEY 3R.

H THEIR ATTORNEY United States Patent 3,181,921 SAFETY AND CONTROLMECHANISM FOR PGWER-OPERATED STRUCTURE Fred W. Moore, Louisville, andRobert C. lPressiey, In, Anchorage, Ky., assignors to General ElectricCompany, a corporation of New York Filed Feb. 3, 1964, Ser. No. 341,8779 Claims. (Cl. 312-223) The present invention relates to power-operatedstructures, and more particularly to a safety and control mechanism forsuch structures.

Many attempts have been made in the past to provide power-operated,movable sections for such apparatus as storage cabinets or the like.However, prior art devices of this type have had deficiencies whichlimited the commercial adoption thereof. One of the principal problemshas been the provision of a satisfactory safety and control mechanism.Such a safety and control mechanism should operate to automatically stopthe movable section of the cabinet structure at its extreme positions.The mechanism also should be manually operable to stop the movablesection intermediate its extreme positions. Additionally, the mechanismshould be responsive to a slight pressure at any point along the lengthof the cabinet to stop the movable section regardless of the relativeposition of the sections to ensure that the users hands or other objectswill not become caught between the edges of the stationary and movablesections as they come together. Prior art devices have failed to achievethese multiple objectives.

A principal object of the present invention is to provide an improvedsafety and control mechanism for a powered cabinet or the like.

Another object of the present invention is to provide a safety andcontrol mechanism for a powered cabinet or the like which is effectiveto automatically stop the movable section of the cabinet at either ofits extreme positions.

A further object of the present invention is to provide a safety andcontrol mechanism for a powered cabinet or the like which is responsiveto a small pressure at any point along the length of cabinet to stop themovable section of the cabinet.

The present invention, in accordance with one form thereof, includes acabinet structure having a stationary cabinet section and an adjacent,power-operated, movable cabinet section. A control and safety mechanismis provided for operating a switch to start and stop the movable cabinetsection. The mechanism includes separate start levers for causing themovable cabinet section to move in opposite directions and a stop memberfor stopping the movement of the movable section. The mechanism isinterconnected with the movable cabinet section so that, as the movablesection approaches either of its extreme positions, the stop memberautomatically functions to stop movement of the movable section.Additionally, a pressure-responsive release mechanism extends along theentire edge of the junction between the movable cabinet section and thestationary cabinet section. The release mechanism responds to a smallpressure exerted at any point along its len th to cause the stop memberto stop movement of the movable cabinet section. This ensures PatentedMay 4, 1965 ice that if any object such as the users hand is insertedbetween the movable cabinet section and the stationary cabinet section,the movable section is immediately stopped to prevent damage to eitherthe object or the cabinet structure.

This invention will be better understood from the following descriptiontaken in conjunction with the accompanying drawings, in which:

FIGURE 1 is a perspective view of a power-operated cabinet including oneembodiment of the present invention, partially broken away and partly incross-section;

FIGURE 2 is a front elevational view of the control and safety mechanismof FIGURE 1, partly broken away and partly in cross-section toillustrate details;

FIGURE 3 is an end view of the mechanism illustrated in FIGURE 2, partlybroken away and partly in crosssection;

FIGURE 4 is an elevational view similar to FIGURE 2, showing one startmember in circuit-closed position;

FIGURE 5 is an end view similar to FIGURE 3 but showing one start memberin the position of FIGURE 4;

FIGURE 6 is a partial perspective view of the pressureresponsive releasemechanism; and

FIGURE 7 is a schematic wiring diagram of the electrical controlcircuit.

Referring to FIGURE 1, there is shown a cabinet structure 10 including astationary cabinet section 11 and a movable cabinet section 17:. Themovable cabinet section 12 is moved upwardly and downwardly by means ofa suitable motor and lift mechanism (not shown). The rear portion of thestationary cabinet section is provided with an upstanding ledge 13 inwhich is mounted a control and safety mechanism 14 which is utilized tostart and stop the motor powering the movable cabinet section in orderto control the positioning of the movable cabinet section.

The structure of the control and safety mechanism will be betterunderstood by reference to FIGURES 2 through 5. A switch 15 is mountedin the stationary cabinet section 11 and extends upwardly into anopening 16 provided in the upstanding ledge 13. The switch is aconventional bistable switch including switch-operating members 17, 13and 19. The switch-operating members are stable in either their upperposition (illustrated in FIGURE 2 by switch-operating members 17 and 18)or their lower position (illustrated in FIGURE 2 by switchoperatingmember 19). When in their lower position, the operating members 17 and18 close contacts (not shown) within the switch 15 to provide electricpower to leads 2t) and 21 respectively and function to open thesecontacts when in their upper position. Switch-operating member 19functions to close contacts (not shown) within the switch to provideelectric power to lead 22 when switch-operating member 19 is in itsupper position and to open its associated contacts when it is in itslower position. The switch-operating members are interconnected withinthe switch so that depression of either of the members 17 and 13 causesthe member 19 to be raised and depression of the member 19 causes themembers 17 and 1% to be raised. It will be understood that, bydepression of the appropriate one of the switch-operating members, theswitch may be set in the off position, in which case no electric powerwill be provided to the leads 2Q, 21

and 22, or electric power may be selectively provided to leads and 22 orleads 21 and 22.

The control and safety mechanism 5 for operating the switch-operatingmembers 17, 18 and 19 is mounted within the opening 16 in the ledge 13and includes a frame 23 which supports the other parts of the mechanism.A first manually-operable start member 24 and a second manually-operablestart member 25 are pivotally mounted within the frame 23. The startmembers are in the form of levers mounted upon a rod 26 which extendsacross and is mounted on the rear of the frame 23. The start members orlevers include downwardly extending projections 27 and 28 which areformed to contact and depress switch-operating members 17 and 18respectively as the start levers are pivoted downwardly about the rod26. A stop member in the form of a vertically movable block 29 ismounted within the frame between the start levers. The stop member 29 ispositioned between a pair of guides or brackets 30 and 31. The guidesinclude inwardly extending shoulders 32 and 33 respectively, whichextend partially across the front of the stop member 29. The guideseffectively constrain the stop member to movement in the verticaldirection. The stop member 29 is mounted about a shaft 34 for verticalmovement and is biased to its lower position by means of a coil spring35. When the stop member is moved to its upper position it compressesthe coil spring against the frame 23, thus storing energy for moving thestop member to its lower position. When moved to its lower position, thestop member 29 depresses switchoperating member 19 to open the circuitthrough switch 15.

The first start lever 24 is interconnected with stop member 29 by meansof a first trip member 36. The trip member 36. The trip member 36 ispivoted at 37 and in- I cludes an extension 38 which contacts theunderside of start lever 24. The opposite end of trip member 36 isformed with a pair of spaced arms 39 and 40. The spaced arms overlie thefront and rear faces of the stop member 29. The arms include inwardlyextending pins 41 and 42 which are received in horizontal slots 43 and44 in stop member 29 to form an operative engagement between trip member36 and stop member 29.

In a similar manner the second start member 25 is interconnected withstop member 29 by means of a second trip member 45. The trip member 45is pivoted at 46 and includes an extension 47 which contacts theunderside of start lever 25. The opposite end of trip member 45 isformed with a pair of spaced arms 48 and 49 which overlie the front andrear faces respectively of stop member 29. The arms include inwardlyextending pins 50 and 51 which are received in horizontal slots 43 and44 in stop member 29 to form an operative engagement between trip member45 and stop member 29.

In order to latch stop member 29 in its upper, or switch closed positionwhen either of start levers 24 or 25 is pivoted downwardly, stop member29 is formed to include a notch 52 which is engaged by a spring latch53. Thus, when either of start levers 24 and 25 is pivoted downwardly todepress one of the switch-operating members 17 and 18, stop member 29 ismoved vertically upward and is latched in its upper position (as shownin FIGURE 5).

In order to disengage spring latch 53 from notch 52 and allow coilspring 35 to move stop member 29 downwardly, spring latch 53 is formedto include a cam arm 54 which is operated by a pressure-responsiverelease mechanism 55. The pressure-responsive mechanism 55 includes aplunger 56 mounted on a leaf spring 57 which is connected to the top offrame 23 (as best seen in FIGURES 2 and 4). The spring 57 biases plunger56 to an upper position but is deformable under pressure to move plunger56 downwardly to engage cam arm 54 and thereby disengage spring latch 53from notch 52.

Referring now to FIGURE 5, it will be seen that an elongated control bar58 is provided for depressing leaf spring 57. In order to maintaincontrol bar 58 parallel to upstanding ledge 13 so that the pressurenecessary to depress leaf spring 57 is the same over the entire lengthof the cabinet, control bar 58 is connected to a control bar supportmember 59 by means of a number of spaced parallel arms 60 which arepivotally secured to control bar 58 and control bar support member 59 bymeans of rivets 61. The control bar support member 59 is in turn securedto upstanding ledge 13.

The control bar 58 includes a horizontal portion 62 which is disposedunder movable cabinet section 12 so as to be contacted by cabinetsection 12 as it approaches its extreme lower position to depress leafspring 57 and to release stop member 29. The horizontal portion 62 isprovided with a pair of extensions 63 and 64 which project outwardlyfrom movable cabinet section 12 adjacent the control and safetymechanism 14 so that the operator may depress the control bar manuallywithout reaching under the edge of the movable cabinet 12.

In order to stop the movable cabinet section 12 as it approaches itsextreme upper position, a stop arm 65 is pivotally mounted on controlbar support member 59. One end 66 of stop arm 65 extends through anopening 67 in control bar 58 while the other end of stop arm 65 isformed with a foot 68 which projects outwardly from control bar supportmember 59. Referring now to FIG- URES 3 and 5, it will be seen that foot68 is disposed above a lower portion 69 of movable cabinet section 12 sothat, as the movable cabinet section approaches its extreme upperposition, lower portion 69 engages foot 68 and pivots stop arm 65 tolower the control bar 58 and depress leaf spring 57 and plunger 56.

FIGURE 7 is a schematic wiring diagram of the electric control circuitin which the switch 70 represents the contacts controlled byswitch-operating member 17, switch 71 represents the contacts controlledby switch-operating member 18 and switch 72 represents the contactscontrolled by switch-operating member 19. The leads 20, 21 and 22connect switches 70, 71 and 72 to the windings of motor 73. Switches 70and 71 are closed by depressing switch-operating members 17 and 18respectively while switch 72 is closed by raising switch-operatingmember 19. The open-circuit or motor-off position indicated by FIGURE 7corresponds to the control and safety mechanism setting shown in FIGURE2.

Downward movement of first start member 24 to depress switch-operatingmember 17 closes contact 70 and the interconnection betweenswitch-operating member 17 and switch-operating member 19 causesswitch-operating member 19 to rise and switch 72 to be closed. With thissetting the motor 73 will rotate so as to move the movable cabinetsection 12 upwardly. A subsequent depression of leaf spring 57 andplunger 56 disengages latch 53 from notch 52 and allows coil spring 35to move stop member 29 to its lower position. This movement of stopmember 29 depresses switch-operating member 19 to open switch 72 and theinterconnection between switchoperating member 19 and switch-operatingmember 17 raises switch-operating member 17 and opens switch 70,stopping upward movement of the movable cabinet section 12.

Downward movement of second start member 25 depresses switch-operatingmember 18 and, in a manner similar to the operation upon downwardmovement of first operating member 24, results in switches 71 and 72being closed to provide electrical power to the motor 73 for movingmovable cabinet section 12 downwardly. A subsequent depression of leafspring 57 and plunger 56 causes a depression of switch-operating member19 and raises switch-operating member 18 to open switches 71 and 72 andstop the movable cabinet section.

Beginning with the cabinets in the position illustrated in FIGURE 1,when it is desired to raise the movable cabinet section 12 the operatormerely depresses first start member 24. The projection 27 depressesswitch-operating member 17 and the extension 38 is rotated downwardly,pivoting first trip member 36 about pivot 37 and moving stop member 2%upwardly. When stop member 29 reaches its uppermost position, latch 53engages the notch 52 and holds stop member 29 in its upper positionagainst the pressure exerted by the compressed coil spring 35. Theinterconnection between switch-operating member 17 and switch-operatingmember 19 causes switchoperating member 19 to be raised asswitch-operating member 17 is depressed, thus closing switches 70 and72. The motor 73 rotates in a direction to raise movable cabinet section12. Since second trip member 45 is interconnected with stop member 29,second trip member 45 also will be pivoted downwardly and second startmember 25 will move downwardly a short distance until extension 28 comesin contact with switch-operating member 18. However, since switch is abi-stable switch, switchoperating members 17 and 18 are biased to bothof their extreme positions and switch-operating member 18 will supportthe weight of second start member 25.

Referring now to FIGURE 6, as movable cabinet section 12 approaches itsupper position, lower portion 69 of the movable section contacts theoutwardly projecting foot 68 and pivots stop arm 43 to depress controlbar 58, thereby depressing leaf spring 57 and plunger 56 and disengaginglatch 53 from notch 52. The stop member 29 is thereby released and coilspring 35 forces stop member 29 downwardly, depressing switch-operatingmember 19. The downward movement of stop member 2h also pivots tripmembers as and 45 to raise start members 24 and 25 and the depression ofswitch-operating member 19 raises switch-operating member 17. Thusswitches 74] and 72 are opened to stop the motor and movable cabinetsection.

In a similar manner when it is desired to lower the movable cabinetsection, the second start member 25 is .moved downwardly and projection28 depresses switchoperating member 18. The second trip member 45 ispivoted about pivot 46 and raises stop member 29 to its upper positionwhere it is locked in place by latch 53. The switch-operating member 18,also being interconnected with switch-operating member 19, raisesswitchoperating member 19 as switch-operating member 18 is depressed andthereby causes switches 71 and 72 to be closed to operate the motor 73in a direction to lower the movable cabinet section 12. As the movablecabinet section 12 approaches its lowermost position, it contacts thehorizontal extension 62 of contact bar 58 and forces it downwardly todepress leaf spring 57 and release stop member 29 from latch 53. Thestop member 29 is then forced downwardly by coil spring and depressesswitchoperating member 19. The downward movement of stop member 29pivots trip members 39 and to raise start members 24 and 25 and thedepression of switch-operating member 19 raises switch-operating member18. Thus switches 71 and 72 are opened and motor 73 and movable cabinetsection 12 are stopped.

Regardless of the direction in which the movable cabinet section ismoving the operator may stop the movable cabinet section by pressingdownwardly on either of extensions 63 and 64. This action depressescontrol bar 58 and releases stop member 29 for downward movement byaction of coil spring 35 to stop the movable section. Additionally, if aforeign object, such as the operators hand or the handle of a kitchenutensil, has been inserted into the movable cabinet section while it isin its raised position and is not removed prior to lowering of themovable section, the pressure exerted on the control bar at any pointalong the length of the cabinet, when the movable section comes intocontact with the foreign object and forces it against the control bar,operates to depress leaf spring 57 and plunger 56 to release stop member29 and stop movement or" the movable section. The parallel armconnection between control bar 58 and control bar support member 59assures that the pressure necessary to release the stop member isuniform over the entire length of the control bar and is only thepressure which is necessary to depress leaf spring 57. Thus the movablecabinet section will automatically stop prior to the time that anydamage is done to a foreign object caught between the two cabinetsections.

Other modifications of this invention will occur to those skilled in theart and it is to be understood, therefore, that this invention is notlimited to the particular embodiment disclosed but that it is intendedto cover all modifications which are within the true spirit and scope ofthis invention as claimed.

What we claim as new and desire to secure by Letters Patent of theUnited States is:

1. For use with a power-operated device, a combination control andsafety mechanism to operate a control switch for the device comprising:

(a) a manually-operated first member to close the switch to start thedevice,

(1)) a second member to open the switch to stop the device when saidsecond member is in a first position,

(0) biasing means to bias said second member to said first position,

(d) means interconnecting said first member and said second member sothat movement of said first memher to close the switch causes saidsecond member to move to a second position and comprising:

(aa) a trip member pivoted intermediate its ends,

(bb) one end of said trip member being engageable by said first member,and

( ce) the other end of said trip member being engageable by said secondmember,

(dd) whereby movement of said first member to close the switch effectspivoting movement of said trip member to move said second member to saidsecond position and movement of said second member to said firstposition resets said first member,

(e) a latch engaging said second member to secure said second member insaid second position, and

(f) a pressure'responsive release mechanism to disengage said latch fromsaid second member,

(g) said biasing means being effective, upon disengagement of said latchfrom said second member, to move said second member to said firstposition to open the switch and stop the device.

2. For use with a power-operated device, a combination control andsafety mechanism to operate a control switch for the device comprising:

(a) a manually-operated first member to close the switch to start thedevice,

(1)) a second member to open the switch to stop the device when saidsecond member is in a first position,

(c) biasing means to bias said second member to said first position,

(d) means interconnecting said first member and said second member sothat movement of said first member to close the switch causes saidsecond member to move to a second position,

(.2) a latch engaging said second member to secure said second member insaid second position, and

(f) a pressure-responsive release mechanism to disengage said latch fromsaid second member and comprising:

(aa) an elongated control bar support member attached to the device,

(bb) an elongated, movable control bar, and

(cc) a plurality of spaced, parallel arms pivotally secured to saidcontrol bar and to said support member for rnovably mounting saidcontrol bar on said support member,

(dd) whereby said control bar remains parallel to said support memberduring movement of said control bar so that the pressure necessary todisengage said latch from said second member is substantially the sameover the entire length length of said control bar,

(g) said biasing means being effective, upon disengagement of said latchfrom said second member, to move said second member to said firstposition to open the switch and stop the device.

3. For use with a power-operated cabinet including a stationary sectionand a vertically movable section mounted for movement with respect tothe stationary section, a combination control and safety mechanism tooperate a control switch for the cabinet, comprising:

(a) a first start member to close the switch to cause the movablesection to move upwardly,

(b) a second start member to close the switch to cause the movablesection to move downwardly,

(c) a stop member to open the switch to stop movement of the movablesection when said stop member is in a first position,

(d) biasing means to bias said stop member to said first position,

(e) means interconnecting said first start member and said stop memberso that movement of said first start member to close the switch causessaid stop member to move to a second position,

(1) means interconnecting said second start member and said stop memberso that movement of said second start member to close the switch causessaid stop member to move to said second position,

(g) a latch engaging said stop member to secure said stop member in saidsecond position, and

(h) a pressure-responsive release mechanism to disengage said latch fromsaid stop member and comprising:

(aa) an elongated control bar support member attached to the cabinet andextending substantially the entire length of the cabinet,

(12b) an elongated, movable control bar extending substantially theentire length of the cabinet, and

(cc) a plurality of spaced, parallel arms pivotally secured to saidcontrol bar and to said support member for movably mounting said controlbar on said support member,

(dd) whereby said control bar remains parallel to said support memberduring movement of said control bar so that the pressure necessary todisengage said latch from said second member is substantially the sameover the entire length r of said control bar,

(i) said biasing means being effective, upon disengagement of said latchfrom said stop member, to move said stop member to said first positionto open the switch and stop movable section.

4. A control and safety mechanism as described in claim 2 wherein saidrelease mechanism also includes a plunger biased away from said latchand movable by said control bar to contact said latch and disengage saidlatch from said second member when pressure is exerted upon said controlbar.

5. A control and safety mechanism as described in claim 3 wherein saidrelease mechanism also includes:

(a) a stop arm pivotally mounted on said support member and having oneend engaging said control bar and further having the other endprojecting from said support member into the path of the movable sectionof the cabinet so that the movable section engages the stop arm as themovable section approaches its extreme upper position for exertingpressure on said control bar to open the switch, and

(b) wherein said control bar is positioned in the path of the movablesection so that the movable section engages the control bar as themovable section aptil 8 proaches its extreme lower position for exertingpressure on the control bar to open the switch.

6. For use with a power-operated cabinet including a stationary sectionand a vertically movable section mounted for movement with respect tothe stationary section, a combination control and safety mechanism tooperate a control switch for the cabinet, comprising:

(a) a first start member to close the switch to cause the movablesection to move upwardly,

(b) a second start member to close the switch to cause the movablesection to move downwardly, (c) a stop member to open the switch to stopmovement of the movable section when said stop member is in a firstposition,

(d) a coil spring biasing said stop member to said first position,

(e) means for compressing said coil springs upon movement of said stopmember to a second position to store energy for moving said stop memberto said first position,

(f) a first trip member pivoted intermediate its ends,

(g) the first end of said first trip member being engageable by saidfirst start lever and the second end of said first trip member engagingsaid stop member so that movement of said first start member to closethe switch causes said stop member to move to said second position,

(It) a second trip member pivoted intermediate its ends,

(i) the first end of said second trip member being engageable by saidsecond start member and the second end of said trip member engaging saidstop member so that movement of said second start member to close theswitch causes said stop member to move to said second position,

(j) a latch engaging said stop member to secure said stop member in saidsecond position, and

(k) a pressure-responsive release mechanism to disengage said latch fromsaid stop member and including,

(an) an elongated control bar support member attached to the stationarysection of the cabinet and extending substantially the entire length ofthe cabinet,

(bb) an elongated, movable control bar extending substantially theentire length of the cabinet,

(cc) a plunger biased away from said latch and movable by said controlbar to contact said latch and disengage said latch from said stop memberwhen pressure is exerted on said control bar, (dd) a plurality ofspaced, parallel arms pivotally secured to said control bar and to saidsupport member whereby said control bar remains parallel to said supportmember during movement of said control bar so that the pressurenecessaryto move said plunger is substantially the same over the entirelength of said control bar, and

(ee) a stop arm pivotally mounted on said support member,

(ff) one end of said stop arm engaging said control bar and the otherend of said stop arm projecting from said support member into the pathof the movable section of the cabinet so that the movable sectionengages said stop arm as the movable section approaches its extremeupper position for exerting pressure on said control bar to move saidplunger into engagement with said latch to disengage said latch fromsaid stop member,

(gg) said control bar being positioned in the path of the movablesection so that the movable section engages said control bar as themovable section approaches its extreme lower position for exertingpressure on said control bar to move said plunger into engagement withsaid latch to disengage said latch from said stop member,

(I) said coil spring being effective, upon disengagement of said latchfrom said stop member, to move said stop member to said first positionto open the switch and stop the movable section.

7. A combination control and safety mechanism as described in claim 6wherein:

(a) said stop member has a slot therein,

(b) said second end of said first trip member includes a pin which isreceived in said slot in said stop member so that movement of said firststart member to close the switch causes said stop member to move-to saidsecond position, and

(c) said second end of said second trip member includes a pin which isreceived in said slot in said stop member so that movement of saidsecond start member to close the switch causes said stop member to moveto said second position.

8. A power-operated cabinet structure comprising:

(a) a stationary cabinet section including an upstanding ledge having anopening therein,

(b) a movable cabinet section mounted adjacent said stationary sectionand overlying said upstanding ledge,

(c) a switch to control movement of said movable section,

(d) a combination control and safety mechanism mounted in said openingin said ledge to operate said switch comprising:

(aa) a first start member to close said switch to cause said movablesection to move upwardly,

(bb) a second start member to close said switch to cause the movablesection to move downwardly,

(cc) a stop member to open said switch to stop movement of the movablesection when said stop member is in a first position,

(dd) biasing means to bias said stop member to said first position,

(ee) means interconnecting said first start member and said stop memberso that movement of said first start member to close said switch causessaid stop member to move to a second position,

(7?) means interconnecting said second start member and said stop memberso that movement of said second start member to close said switch causessaid stop member to move to said second position, and

(gg) a latch engaging said stop member to releasably secure said stopmember in said second position,

(hh) said biasing means being effective, upon disengagement of saidlatch from said stop member to move said stop member to said firstposition to open said switch and stop said movable section, and

(e) a pressure-responsive release mechanism for disengaging said latchfrom said stop member comprismg:

(an) an elongated control bar support member attached to said upstandingledge and extending substantially the entire length of said cabinet,

(bb) an elongated control bar movably mounted on said support member,

(cc) said control bar having a portion disposed adjacent the uppersurface of said ledge for contact by said movable section toautomatically stop said movable section, and

(dd) said control bar including an extension projecting outwardly fromsaid movable section adjacent said control and safety mechanism wherebythe operator may depress said control bar to stop said movable sectionwithout reaching under said movable section.

9. A power-operated cabinet including:

(a) a stationary cabinet section,

(b) a movable cabinet section mounted for movement with respect to saidstationary section,

(0) a switch to control the movement of said movable section,

(d) a first start member to close said switch to cause said movablesection to move upwardly,

(e) a second start member to close said switch to cause said movablesection to move downwardly, (f) a stop member to open said switch tostop movement of said movable section when said stop member is in afirst position,

(g) a coil spring biasing said stop member to said first position,

(11) means to compress said coil spring upon movement of said stopmember to a second position to store energy for moving said stop memberto said first position,

(i) said stop member having a slot therein,

(j) a first trip member pivoted intermediate its ends,

(k) one end of said first trip member being engageable by said firststart member and the other end of said first trip member including a pinreceived in said slot in said stop member so that movement of said firststart member to close said switch causes said stop member to move saidsecond position,

(I) a second trip member pivoted intermediate its ends,

(in) one end of said second trip arm being engageable by said secondstart member and the other end of said second trip member including apin received in said slot in said stop member so that movement of saidsecond start member to close said switch causes said stop member to moveto said second position,

(it) a latch engaging said stop member to secure said stop member insaid second position, and

(0) a pressure-responsive release mechanism to disengage said latch fromsaid stop member, comprismg:

(aa) an elongated control bar support member attached to said stationarycabinet section and extending substantially the entire length of saidcabinet,

(bb) an elongated, movable control bar extending substantially theentire length of said cabinet,

(cc) a plunger biased away from said latch and movable by said controlbar to contact said latch and disengage said latch from said stopmember,

(dd) a plurality of spaced, parallel arms pivotally secured to saidcontrol bar and to said support member whereby said control bar remainsparallel to said support member during movement of said control bar sothat the pressure necessary to move said plunger is substantially thesame over the entire length of said control bar, and

(ee) a stop arm pivotally mounted on said support member,

(ff) one end of said stop arm engaging said control bar and the otherend or said stop arm projecting from said support member into the pathof said movable cabinet section so that said movable cabinet sectionengages said stop arm as said movable cabinet section approaches itsextreme upper position to exert pressure on said control bar to movesaid plunger into engagement with said latch to disengage said latchfrom said stop member,

(gg) said control bar being positioned in the path of said movablesection so that said movable 1 1 12 section engages said control bar assaid mov- References Cited by the Examiner able section approaches itsextreme lower posi- UNITED STATES PATENTS tion to exert pressure on saidcontrol bar to remove said plunger into engagement with said 2429152310/47 Murphy 312 312 X latch to disengage said latch from said stop 542825616 3/58 9 312 223 Ember, if)??? 523 d "5 3, 3. X

s 'd co'l s rin b ff ctive, u d en a e- 2 W00 War 23 X (P) m 1 p g mg 66 18 g g 3,116,910 1/64 Moore et nl 254-126 ment of said latch from saidstop member, to move said stop member to said first position to opensaid FRANK SHERRY, 'Y Examine!- switch and stop said movable section ofsaid cabinet. 10' CHANCELLOR E, HARRIS, Examiner.

1. FOR USE WITH A POWER-OPERATED DEVICE, A COMBINATION CONTROL ANDSAFETY MECHANISM TO OPERATE A CONTROL SWITCH FOR THE DEVICE COMPRISING:(A) A MANUALLY-OPERATED FIRST MEMBER TO CLOSE THE SWITCH TO START THEDEVICE, (B) A SECOND MEMBER TO OPEN THE SWITCH TO STOP THE DEVICE WHENSAID SECOND MEMBER IS IN A FIRST POSITION, (C) BIASING MEANS TO BIASSAID SECOND MEMBER TO SAID FIRST POSITION, (D) MEANS INTERCONNECTINGSAID FIRST MEMBER AND SAID SECOND MEMBER TO THAT MOVEMENT OF SAID FIRSTMEMBER TO CLOSE THE SWITCH CAUSES SAID SECOND MEMBER TO MOVE TO A SECONDPOSITION AND COMPRISING: (AA) A TRIP MEMBER PIVOTED INTERMEDIATE ITSENDS, (BB) ONE END OF SAID TRIP MEMBER BEING ENGAGEABLE BY SAID FIRSTMEMBER, AND (CC) THE OTHER END OF SAID TRIP MEMBER BEING ENGAGEABLE BYSAID SECOND MEMBER, (DD) WHEREBY MOVEMENT OF SAID FIRST MEMBER TO